International gravimetric connections were carried out by means of several LaCoste & Romberg gravimeters (model G) at selected cities mainly along the Circum-Pacificzone from 1979 to 1982. This article deals with a measuring error caused by the setting error of the LaCoste & Romberg gravimeter to evaluate an accuracy of gravity measurements performed throughout the present investigations. It was found through the early stage of the investigations that a mechanical sensitivity of the gravimeter was significantly changed with correlated to mean air temperature in each city. A critical examination on this problem was made in the late stage of the investigations. The result of the examination revealed that the sensitivity change was brought from a characteristic common to the LaCoste & Romberg gravimeter by which an optimal offset angle of the gravimeter at the time of gravity measurements depends on gravity value at each measuring station. This characteristic of the gravimeter can be explained by the relative change of hinge positions in the spring system and does not affect any measuring accuracy. The setting error of the gravimeter at each gravity measurement, that was represented by the discrepancy between a setting angle and the optimal angle in offset angle, was determined by arranging both data of sensitivity measurements made at each measuring station and those of calibration results obtained at several stations. It was confirmed that the measuring error caused by the setting error of the gravimeter was small; namely, less than 0.01 mgals usually and 0.02 mgals at maximum throughout the whole period of the investigations.
